Solvent-free process for the synthesis of energetic oxetane monomers

Abstract

This invention relates to a process for the preparation of mono- and bis(azidomethyl)oxetanes. These compounds are prepared by combining a mono- or bis-X-oxetane (wherein X is, for example, a tosylate, mesylate, halogen, etc.) with an aqueous solution of a metallic azide and a phase transfer catalyst. Mono- and bis(azidomethyl)oxetanes can be polymerized to form homopolymers and copolymers with load bearing polyether backbones and highly energetic pendant groups. Such homopolymers and copolymers of the present invention are useful as energetic binders in high-energy formulations, such as propellants, explosives, and gasifiers.

What is claimed is: 
     
       1. A process for the preparation of a compound having the formula ##STR8## said process comprising: (a) combining a compound having the formula ##STR9##  in which R 1  and R 2  are members independently selected from the group consisting of tosylate, mesylate and halogens with an aqueous solution of a metallic azide and a phase transfer catalyst to form a product mixture; and (b) recovering compound I from said product mixture.   
     
     
       2. A process in accordance with claim 1 wherein R 1  and R 2  are halogens. 
     
     
       3. A process in accordance with claim 2 wherein R 1  and R 2  are both Cl. 
     
     
       4. A process in accordance with claim 2 wherein R 1  and R 2  are both Br. 
     
     
       5. A process in accordance with claim 1 wherein said aqueous solution of said metallic azide is an aqueous solution of sodium azide. 
     
     
       6. A process in accordance with claim 5 wherein said aqueous solution of sodium azide is about 20% to about 50% sodium azide. 
     
     
       7. A process in accordance with claim 1 wherein said phase transfer catalyst is a member selected from the group consisting of quaternary ammonium salts, quaternary phosphonium salts, polyethers and crown ethers. 
     
     
       8. A process in accordance with claim 7 wherein said phase transfer catalyst is a quaternary ammonium salt selected from the group consisting of tetramethylammonium halides and tetra-n-butylammonium halides. 
     
     
       9. A process in accordance with claim 1 wherein step (a) is carried out at a temperature ranging from about 90° C. to about 110° C. 
     
     
       10. A process in accordance with claim 1 wherein step (a) further comprises the addition of a member selected from the group consisting of sodium hydroxide, sodium bicarbonate, sodium carbonate, potassium hydroxide and potassium carbonate. 
     
     
       11. A process for the preparation of a compound having the formula ##STR10## in which R 1  is a member selected from the group consisting of H, lower alkyl, alkoxy, OH, NF 2 , ONO 2 , NO 2 , said process comprising: (a) combining a compound having the formula ##STR11##  in which R 2  is a member selected from the group consisting of mesylate, tosylate and halogens with an aqueous solution of a metallic azide and a phase transfer catalyst to form a product mixture; and   (b) recovering compound III from said product mixture.   
     
     
       12. A process in accordance with claim 11 wherein R 2  is a halogen. 
     
     
       13. A process in accordance with claim 12 wherein R 2  is Cl. 
     
     
       14. A process in accordance with claim 12 wherein R 2  is Br. 
     
     
       15. A process in accordance with claim 11 wherein said aqueous solution of said metallic azide is an aqueous solution of sodium azide. 
     
     
       16. A process in accordance with claim 15 wherein said aqueous solution of sodium azide is about 20% to about 50% sodium azide. 
     
     
       17. A process in accordance with claim 11 wherein said phase transfer catalyst is a member selected from the group consisting of quaternary ammonium salts, quaternary phosphonium salts, polyethers and crown ethers. 
     
     
       18. A process in accordance with claim 17 wherein said phase transfer catalyst is a quaternary ammonium salt selected from the group consisting of tetramethylammonium halides and tetra-n-butyl-ammonium halides. 
     
     
       19. A process in accordance with claim 11 wherein step (a) further comprises the addition of a member selected from the group consisting of sodium hydroxide, sodium bicarbonate, sodium carbonate, potassium hydroxide and potassium carbonate.